The present invention relates, in general to sewing machines and in particular to a top transport sewing machine having a feeder foot and a fabric presser foot where the presser foot alternatingly interacts with the feeder foot. A coupling member is driven by an eccentric through a transmission via a triangular lever linked to the coupling member, for imparting, to the feeder foot and presser foot, up and down motions directed perpendicularly to a stitch plate, and in which the speed of the up and down motion approaches zero during a touch down phase of the feet.
A known top transport sewing machine is disclosed in U.S. Pat. No. 4,116,145. The uneven lifting motion in this machine is disadvantageously generated by a slide-push guide arrangement. This slide-push guide is not only difficult to manufacture, but also has unfavorable operating characteristics and is subject to great wear which can be reduced only by sophisticated lubrication. Since the top transport mechanism and its drive are housed in the head of the machine, in which a full lubrication system cannot be provided for known reasons, the use of a slide push guide within this drive is problematical for high-speed sewing machines.